Toronto Subway is based on the lettering originally used for station identification and signs by the Toronto Transit Commission (TTC) in the Toronto, Canada, subway system. The first subway line opened in 1954. Over the years and subsequent expansion of the subway, the signs became corrupted by the use of other typefaces such as Helvetica and Gill Sans. However, the original lettering remains unique. The lettering on the original signage consists only of uppercase characters and a few bits of punctuation in two weights — the Regular and Bold.

The Toronto Subway fonts were developed from rubbings of the lettering etched into station walls and photographs of painted signs. The overall style of the lettering is very mechanical, almost naive, yet still having a certain amount of elegance. This style was followed as much as possible in creating the extra lowercase, punctuation and other special characters.

The Toronto Subway family was expanded in 2014 with the addition of the Light and Black weights.